In spite of the wide and mature karaoke technology and application thereof, there are few portable simplified devices and even fewer individualized karaoke products, such that karaoke can be used only in special places or fixed places, causing much inconvenience. Moreover, various existing microphones, including microphones having a karaoke reverberation function, have mature technology and wide application, but the microphone is usually a separate, stand-alone microphone product and must be used with an external sound box or other devices. Because the sound box generates, along with the sound, vibration having the same frequency as that of the sound, when the microphone is integrated with or close to the sound box, the sound input from the microphone is amplified by the sound box and then transmitted to the microphone through the housing. The microphone then again inputs and amplifies the sound of the same frequency, and a strong self-feedback effect, that is, self-excitation effect, is produced after repeated amplification many times. At this time, the sound box produces a persistent and continuously strengthened sound of the same frequency (referred to herein as a squeal), completely disrupting the normal use.
Existing designs change the frequency of the sound to make the frequency or frequency phase of the input sound different from the output frequency or frequency phase, thereby avoiding squealing, or remove specific frequencies and so on through actual application or calculation, so as to avoid squealing. However, all these methods cause serious distortion of sounds and cannot meet requirements for desirable sound quality.
Therefore, integration of a microphone and a sound box to achieve portability and a direct karaoke effect, and to enable people to enjoy singing and enjoy the fun of music at any time and any place, with unchanged or even improved sound quality, is an aspiration of many people.